The control of insects and particularly biting flies has been a problem in livestock husbandry. One method of controlling insect populations has been the development of several types of sustained release insecticide application devices which can be attached to the ears and the mane of animals to keep such insects away from that part of the body. Also time released insecticides have been attached by various methods to the switch of the tail so that portions of the back and flank of the animals can be protected. An insecticide blanket for destroying grubs in cattle has even been developed which is glued to the hair of the hide to keep the same in place.
The head and shoulders are the usual site of choice for most biting pests of cattle and the ear and mane tags have been largely successful in detering bites in this area. The biting pest populations, as a result of the above, have simply relocated to the rear and underside of cattle with a preference for the tender, unhaired skin surfaces of the utter and teats in females and the scrotum in males.
In recent years mastitis has become a most costly disease of dairy heifers. This disease occurs when bacteria penetrates the teat orifice, colonize in the teat canal keratin, and gain entry into the mammary gland. In spite of growth inhibitory properties of the keratin, bacteria are able to survive in the teat canal and progress into the udder, causing inflammation.
Current methods of mastitis control advocate adoption of management practices developed for mature lactating and dry cows, and include teat dipping, dry cow therapy, proper use of functionally adequate milking machines, proper treatment of clinical cases, and culling of chronically infected animals. First calf heifers which are infected before calving often are culled because of the chronic nature of mastitis induced by biting insects which goes undetected.